My tut that I brought from 7s over here.
How to tell what type of xbox 360 wireless controller board you have. Credit goes towards consolecustoms for the back pics of the controller. The rest I found off google.
If you took yours apart here is a way how to tell what board it is from the front. Look for a little black chip where the sync button is,look at the 1st player led and it should say “d21”, and then take off the thumbstick and look at where the analog stick unit is and you will see little white squares around it.
Here is how to tell what board it is from the front. Look where the sync button is and you will no little black chip up there, look at the 1st player led to see a “d1”, and last look at the analog stick to see circles going around it.
Now this board is a bit tricky because from the front it just looks like a cg board so you will have to look on the back to tell what board it is. One big way to tell if it is a cg2 board is this(Circled in red) will be straight and not tilted like the cg board.